Ultrasonic welding tongs of the kind mentioned above are used in particular for the welding of ends on metallic pipes, such as fluid lines on cooling units, i.e. in particular in air conditioners or refrigerators, for example. This type of welding of ends is performed after a cooling circuit comprising the fluid lines has been filled with a coolant, in such a manner that a filling armature arranged on a free end of the pipe is severed from the pipe end at the same time as said end is being welded.
Although the actual welding process takes place between the welding jaws, which are relatively small and narrow and which, owing to their narrow and small design, allow positioning in the welding position even in the most constricted of spaces in order to also be able to perform the welding process very closely to the unit equipped with the fluid line, the arrangement of the ultrasonic device comprising the sonotrode on a tongs part of the ultrasonic welding tongs requires an overall large-volume design of the ultrasonic welding tongs including a corresponding mass. Hence, for handling of the ultrasonic welding tongs, the ultrasonic welding tongs have to be combined with a handling device so as to compensate the weight of the ultrasonic welding tongs and to thus facilitate handling of the ultrasonic welding tongs.
Although the known ultrasonic welding tongs are provided with a handling device of this kind, thus being easy to position using only one hand, the known ultrasonic welding tongs are supposed to be operated using two hands for safety reasons. This is to ensure that no hand of the operator is located in the area of the welding jaws during performance of the welding process. For two-hand operation, two trigger switches for triggering the welding process are provided, each of which is arranged on one handle, both hands of the operator thus having to be placed on spaced-apart handles in order to perform or trigger the welding process.
Hence, in practice, welding the ends of a tubular fluid line of a cooling unit requires particular skill of the operator because simultaneously to the welding process, he or she has to ensure that the filling armature, which will be severed from the fluid line when the ends are welded, is positioned in a desired location and will in particular not be damaged when dropping into a receiving container.